Fourteen cohort studies provided information on causes of death and were included in analyses presented in this paper. All studies that joined the collaboration have been approved by their local ethics committees or institutional Selisistat review boards, use standardized methods of data collection, and schedule follow-up visits at least once every 6 months. Patient selection and data extraction were performed at the

data centres of the participating cohort studies. Anonymized data from each cohort on a predefined set of demographic, laboratory and clinical variables were pooled and analysed centrally. Data managers checked for duplicated records, and ensured that patients included in more than one cohort had only one record in the combined data set. The primary endpoint in this study was HIV disease progression, defined as (1) a new AIDS-defining disease [based on the clinical part of the 1993 US Centers for

Disease Control and Prevention (CDC) revision of the AIDS case definition] or (2) death from any cause. We utilized an intent-to-continue-treatment approach, and therefore ignored changes to treatment regimen, including treatment interruptions see more and terminations. We measured time from the initiation of cART to the date on which the endpoints occurred. Patients who remained alive were censored at their last visit plus 50% of the average time between visits for that cohort. For example, if a cohort had, on average, 6 months between follow-up visits, patients who did not die would be censored at last visit plus 3 months. This allocates follow-up time in an unbiased way to those who did not die, as the average time from last follow-up to death in those who died is approximately 50% of the interval between scheduled visits.

The secondary outcomes in this study were causes of death. All deaths with International Classification of Diseases (ICD) version 9 or ICD10 or free text coding were reviewed by a computer program and also by a clinician and an either epidemiologist and then reviewed in committee when discordant. Cause of death was determined utilizing a standardized protocol developed by the Copenhagen HIV Programme for coding causes of death in HIV-positive individuals [25]. Two cohorts participating in ART-CC [Italian Cohort of Antiretroviral-Naïve Patients (ICONA) and the Veterans Aging Cohort Study (VACS)] did not provide causes of death and were omitted from analyses. The two cohorts from Germany did not provide cause of death prior to 2002 for patients in Frankfurt and prior to 2003 in Cologne and Bonn clinics. Patients enrolled in these cohorts prior to these years were excluded.